Kevin Schiefelbein
Memorial Sloan Kettering Cancer Center
Leveraging Novel Chemical Biology Tools to Study the Mechanistic Role of Histone H3 Monoaminylation in Neurons
Gene expression in the brain is regulated not only by DNA sequence but also by epigenetic modifications, including post-translational modifications of histones. Among these, monoaminylation by neurotransmitter amines has emerged as a novel class of epigenetic marks. These modifications occur primarily at glutamine 5 of histone H3 and are dynamically regulated by transglutaminase 2, influencing processes such as stress responses, circadian rhythms, and addiction-related behaviors. Despite their emerging importance in neuronal function, the molecular mechanisms underlying histone monoaminylations and their causal role in epigenetic regulation have yet to be defined. Protein trans-splicing provides a powerful strategy to generate full-length, site-specifically modified histones by ligating synthetic peptides bearing defined modifications to the remainder of the protein in its native context. Here, we aim to leverage protein trans-splicing in cells and in vivo to directly interrogate the functional consequences of histone monoaminylations in chromatin architecture, transcription, and neuronal cell fate. In particular, we synthesize monohistaminylated H3 in neurons and mouse brains to determine its impact on transcriptional regulation and behavioral phenotypes. This study deepens our mechanistic understanding of monoaminylation as an epigenetic signal in neurons. Moreover, establishing protein trans-splicing in animal models provides a generalizable platform to investigate defined histone modifications across tissues and disease contexts, opening avenues for therapeutic intervention and clarifying how dysregulated epigenetic signaling contributes to neurological disorders.
Gene expression in the brain is regulated not only by DNA sequence but also by epigenetic modifications, including post-translational modifications of histones. Among these, monoaminylation by neurotransmitter amines has emerged as a novel class of epigenetic marks. These modifications occur primarily at glutamine 5 of histone H3 and are dynamically regulated by transglutaminase 2, influencing processes such as stress responses, circadian rhythms, and addiction-related behaviors. Despite their emerging importance in neuronal function, the molecular mechanisms underlying histone monoaminylations and their causal role in epigenetic regulation have yet to be defined. Protein trans-splicing provides a powerful strategy to generate full-length, site-specifically modified histones by ligating synthetic peptides bearing defined modifications to the remainder of the protein in its native context. Here, we aim to leverage protein trans-splicing in cells and in vivo to directly interrogate the functional consequences of histone monoaminylations in chromatin architecture, transcription, and neuronal cell fate. In particular, we synthesize monohistaminylated H3 in neurons and mouse brains to determine its impact on transcriptional regulation and behavioral phenotypes. This study deepens our mechanistic understanding of monoaminylation as an epigenetic signal in neurons. Moreover, establishing protein trans-splicing in animal models provides a generalizable platform to investigate defined histone modifications across tissues and disease contexts, opening avenues for therapeutic intervention and clarifying how dysregulated epigenetic signaling contributes to neurological disorders.
